Unless otherwise indicated herein, the description in this section is not prior art to the claims in this application and is not admitted to be prior art by inclusion in this section.
Typically, there is known an image forming apparatus such as a multifunctional peripheral (MFP) that can print a document and an image. In particular, in an image forming apparatus for color printing, toner images in respective colors in which electrostatic latent images are exposed by a laser or similar method are developed are once superimposed on an intermediate transfer belt of a transfer unit and then transferred to a recording sheet at a time.
As a typical image forming apparatus using the transfer unit, there is a technique that performs correction using at least one or more reference position marks disposed at an intermediate transfer belt such that the transfer position of a toner image to a transfer material is not displaced from a predetermined transfer position even when the perimeter of the intermediate transfer belt changes with time or when there is an individual difference in perimeter of the intermediate transfer belt during production.